Tilting corona shield



April 8, 1969 J. c. BECK Y TILTING CORONA SHIELD Filed July 12, 1967 I NVENTOR. Jab/r [f Bea/f United States Patent 3,437,741 TILTING CORONASHIELD John C. Beck, Birmingham, Ala., assignor to Bethea Company, Inc.,a corporation of Alabama Filed July 12, 1967, Ser. No. 652,764 Int. Cl.H01b 17/48 U.S. Cl. 174-141 6 Claims ABSTRACT OF THE DISCLOSUREBackground of the invention As is well known in the art to which myinvention relates, one of the principal problems in transmission linemaintenance is the handling of corona shields during maintenance work.This is especially true since it is the usual practice to work onelectrical lines while energized so as not to interrupt service.Heretofore, corona shields have been attached to the yoke or attachmentassembly by means of bolts whereby the entire corona shield had to beremoved while working on assemblies, such as dead end assemblies. Whileslots have been provided in mounting brackets for the corona shieldswhich eliminate the necessity of having to remove the mounting boltsentirely from the assembly, it has still been necessary to remove thecorona shield to provide access to the line end insulators for the linetools. Complete removal and replacement of the corona shields is notonly troublesome and costly but is extremely hazardous.

Brie] summary of invention My improved invention relates to a tiltingcorona shield which is carried by the yoke assembly connecting theinsulator string to a conductor. The corona shield is mounted forpivotal movement relative to the yoke assembly. Cooperating stop membersare carried by the yoke assembly and an adjacent portion of the coronashield end are engageable with each other upon a predetermined amount ofrotation of the corona shield relative to the yoke assembly. Releasableretaining members secure the corona shield at selected angular positionsrelative to the yoke assembly. During maintenance, it is only necessaryto loosen the retaining bolts and then tilt the shield out of the way.When maintenance is complete, the shield is 'tilted back whereupon stopmembers properly align the corona shield. The retaining members thensecure the shield in place.

Apparatus embodying features of my invention is illustrated in theaccompanying drawing, forming a part of this application, in which:

FIG. 1 is a top plan view showing a corona shield mounted on a yokeassembly connecting a single insulator string and a conductor, thecorona shield being shown in the tilted, inoperative position in dottedlines;

FIG. 2 is a side elevational 'view of the apparatus shown in FIG. 1;

FIG. 3 is an enlarged, sectional view taken generally along the line 3-3of FIG. 2;

FIG. 4 is a sectional view taken generally along the line 44 of FIG. 3;

FIG. 5 is a top plan view showing a modified form of my invention; and,

3,437,741 Patented Apr. 8, 1969 FIG. 6 is an isometric view showinganother modified form of my invention. Referring now to the drawing fora better understandmg of my invention, I show a yoke assembly 10 havinga clevlsmember 11 at one side thereof and an eye member 12 at the otherside thereof. The clevis member 11 is pivotally connected by a pin 13 toone end of a link 14. The other end of the link 14 is connected to anadjacent end of an insulator string indicated generally at 16. The eyemember 12 is pivotally connected by a pin 17 to a dead end clamp 18which in turn is secured to a conductor 19 by retaining bolts 21. Theapparatus for connecting the conductor 19 to the insulator string 16thus described is conventional type apparatus and may asssume variousforms. My improved means for mounting the corona shield on the yokeassembly will now be described.

As shown in FIGS. 3 and 4, the yoke assembly 10 is provided with a bodyportion 22 having a groove 23 therein for receiving the ends 24 and 26of a corona shield 27. The portion of the body 22 having the groove 23therein thus forms a clamping element which cooperates with a secondclamping element 28. A groove 29 is provided in the clamping element 28in position to engage the opposite side of the ends 24 and 26 from theends thereof engaged by the groove 23, as shown in FIGS. 3 and 4. Theends 24 and 26 are spaced from each other, as shown in FIG. 3 andretaining members, such as bolts 31, extend through openings 32 inclamping element 28 and threaded openings 33 in clamping element 22 toclamp the ends 24 and 26 of the corona shield there'between.

As shown in FIGS. 3 and 4, the end 24 of the corona shield 27 is cutaway as at 34 to provide angularly spaced stops 36 and 37. Formedintegrally with the inner surface of the body 22 is an inwardlyprojecting detent 38 having stop surfaces 39 and 41 which intersect eachother at the axis of rotation of the ends 24 and 26 of the coronashield. The stop surfaces 39 and 41 are thus spaced angu larly from eachother whereby the stop surface 39 engages the stop 36 upon rotating thecorona shield 27 to the solid line position shown in FIG. 4. Uponrotating the corona shield 27 to the dotted line position shown in FIG.4, the stop 37 engages the stop surface 41. With the ends 24 and 26engaging the grooves 23 and 29 in the clamping elements 22 and 28, theend portions 24 and 26 define shaft-like supporting members for thecorona shield 10.

In FIG 5 of the drawing, I show a modified form of my invention in whicha pair of insulator strings 16 are secured to a pair of conductors 19 bya yoke asembly indicated generally at 10a. Pins 13 pivotally connect oneside of the yoke assembly 10a to links 14 which in turn are connected tothe insulator strings 16. Pins 17 pivotally connect the other side ofthe yoke assembly 10a to links 42 which in turn are pivotally connectedto dead end clamps 18. Instead of clamping both ends of the coronashield between a single pair of clamping elements, in FIG. 5, I show acorona shield 27a which is generally loopedshaped with the ends thereofspaced from each other, as shown. The yoke assembly 10a is provided withbody portions 22 adjacent each end thereof which in turn are providedwith clamping grooves 23, as described hereinabove. In like manner,clamping elements 28 are secured to the body portions 22 by retainingbolts 31 and a clamping groove 29 is provided in the undersurface ofclamping element 28.

In FIG. 6 of the drawing, I show another modification of my invention.In this modification the corona shield proper 2717 may be generallyU-shaped, as shown. The yoke, 10b is provided with a pair of oppositelydisposed brackets 43, each having an upturned portion 44. The coronashield is mounted for pivotal movement relative to the yoke by means ofshaft-like supporting elements or pins 24b and 26b which are secured tothe shield and extend through holes provided in the bracket portions 44.An arcuate slot 46 is provided in each of the bracket portions 44, asshown. The are of the slot 46 is concentric with the hole through whichpin 24b or 26b passes. A stop element 47, which may be a stud extendinginwardly of the shield or a bolt secured in a threaded hole in theshield, is provided in position to pass through the slot 46. The ends ofthe slot 46 cooperate with the sides of the stop element thereby formingstops corresponding to those formed by detent 38 and the cut awayportion 34 in the previously described embodiments of my invention. Areleasable clamping or retaining element, which may be a nut threaded onthe stud forming element 47 or it may be the head of a bolt formingelement 47, is provided whereby the shield is secured in an operativeposition and may be released for movement or to an inoperative position.The yoke 10b shown in FIG. 6 corresponds with the yoke 10 shown in FIG.1, and has a clevis member 1112 at one side and an eye member 12b at theother side. These yokes are typical of attachment assemblies which maybe used between the conductor and insulator strings.

From the foregoing description, the operation of my improved apparatuswill be readily understood. The shaftlike supporting end portion 24 and26 of the corona shield 27 are inserted between the clamping elements 22and 28, as shown in FIGS. 3 and 4 whereby they engage the clampinggrooves 23 and 29. The retaining bolts 31 are moved into threadedengagement with the openings 33 whereupon the corona shield is adaptedto move selectively to the solid line or operative position and thedotted line or inoperative position. At the time of installation, thecorona shield 27 is moved to the solid line position shown in FIGS. 1and 2 whereby the stop 36 engages the stop surface 39 to thus positionthe corona shield accurately relative to the yoke assembly and insulatorstring. With the corona shield 27 properly aligned, the retaining bolts31 are tightened whereby the clamping elements 22 and 28 secure thecorona shield 27 fixedly in the solid line or operative position.

During maintenance of the line, the worker merely loosens the retainingbolts 31 whereby the shaft-like supporting end portions 24 and 26 areadapted to rotate relative to the clamping grooves 23 and 29. The coronashield 27 is then pivoted to the dotted line or inoperative positionshown in FIGS. 1 and 2. In this position, the corona shield is out ofthe way as the line is repaired. When maintenance is complete, thecorona shield 27 is tilted back to the solid line or operative positionshown in FIGS. 1 and 2 and the bolts 31 are retightened. The built-instops 36-39 and 37-41 provide proper positioning and alignment of thecorona shield 27 as it is moved selectively to the operative andinoperative positions.

The operation of the apparatus shown in FIG. -is substantially the sameas the operation of the apparatus shown in FIGS. 1 through 4,'theprincipal difierence being the fact that the ends 24 and 26 aresecuredby separate pairs of clamping elements in the embodiment shown in FIG.5.

While I have shown my invention in several forms, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifictaions without departing fnom thespirit thereof,

4 and I desire, therefore, that only such limitations shall be placedthereupon as are specifically set forth in the appended claims.

What I claim is:

1. The combination with an insulator and a conductor supported thereby,of:

(a) a corona shield between the insulator and the conductor and having ashaft-like supporting element,

(b) cooperating stop members carried by an attachment assembly and thecorona shield engageable with each other upon a predetermined amount ofrotation of said shield relative to said assembly, and

(c) releasable retaining members adapted to secure said corona shield atselected angular positions relative to said assembly and captively mountthe shield between the insulator and the conductor for movement towardand away from the insulator whereby the insulator may be made accessiblefor replacement or servicing upon movement of the shield away from theinsulator.

2. The combination with a yoke assembly connecting at least oneinsulator string to a conductor:

(a) a corona shield having a shaft-like supporting portion,

(b) releasable clamping elements carried by the yoke assembly disposedto receive said shaft-like supporting portion,

(c) cooperating stop mmebers carried by the yoke assembly and saidshaft-like supporting portion engageable wtih each other upon apredetermined amount of rotation of said shaft-like supporting portionrelative to said yoke assembly, and

(d) releasable retaining members securing said clamping elements to eachother with said shaft-like supporting portion clamped therebetween toretain said corona shield at selected angular positions relative to saidyoke assembly.

3. The combination defined in claim 2 in which the end of saidshaft-like supporting portion is cut away to provide angularly spacedstops and a detent is carried by the yoke assembly intermediate saidstops to limit angular rotation of said shaft-like supporting portionrelative to the yoke assembly.

4. The combination defined in claim 2 in which the corona shield is asingle length of generally looped-shaped tube with the ends thereoffitting between said clamping elements.

5. The combination defined in claim 4 in which both ends of the coronashield are clamped between a single pair of clamping elements carried bythe yoke assembly with said retaining members passing between said endsof the corona shield.

6. The combination defined in claim 4 in which each end of the coronashield is clamped by a separate pair of spaced apart clamping elementscarried by the yoke assembly.

References Cited UNITED STATES PATENTS 1,407,477 2/1922 Plimpton.

LARAMIE E. ASKIN, Primary Examiner.

U.S. Cl. X.R. 174144

